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The integration of fast pyrolysis (FP) and biomass pretreatment processes (eg demineralization, torrefaction, drying, etc.) is an effective way of controlling the composition of pyrolysis vapors to obtain bio-oils of higher quality. Accordingly, this study focusses on analysing the effects of leaching sugarcane trash (SCT) and sugarcane bagasse (SCB) with citric acid (CA) on the yields and chemical composition of FP products. The effectivity of CA as a leaching solution was compared to other solutions, commonly used with the same purpose (ie water or solutions of HCl, H2SO4). The efficiency of the leaching pretreatment was analyzed on the basis of the alkali and alkaline earth metals contents in the biomass. These inorganics affect the quality of the produced bio-oil, by catalysing depolymerisation and other degradation processes taking place during bio-oil storage. Approximately 100 g of biomass were demineralized at fixed conditions (25 C and 1 h of leaching time). Pyrolysis trials were carried out in a lab scale fluidized bed reactor at 500 C in inert gas atmosphere (N2) with 1.5 kg pure silica sand as the bed material. The products obtained from FP were divided into liquids (ie, organics and water), the char and the non-condensable gases. Results from the pyrolysis of SCT leached with CA or the reference acids (ie, solutions of HCl, H2SO4) reveal higher yields (44-50 wt.%) of the organic fractions compared to those from untreated and water–leached (33 wt.%) feedstock, butlower yields of water and char (about 11 and 15 wt.%, respectively). Meanwhile, the yields of non-condensable gases (NCGs) stay below 25 wt.%. This fraction is composed …